Download or read book Report on 238Pu(n, X) Surrogate Cross Section Measurement written by and published by . This book was released on 2010 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this year's effort is to measure the 238Pu(n, f) and 238Pu(n,2n) cross section from 100 keV to 20 MeV. We designed a surrogate experiment that used the reaction 239Pu(a, a(prime)x) as a surrogate for 238Pu(n, x). The experiment was conducted using the STARS/LIBERACE experimental facility located at the 88 Inch Cyclotron at Lawrence Berkeley National Laboratory in January 2010. A description of the experiment and status of the data analysis is given. In order to obtain a reliable 238Pu(n, x) cross section we designed the experiment using the surrogate ratio technique. This technique allows one to measure a desired, unknown, cross section relative to a known cross section. In the present example, the 238Pu(n, x) cross section of interest is determined relative to the known 235U(n, x) cross section. To increase confidence in the results, and to reduce overall uncertainties, we are also determining the 238Pu(n, x) cross section relative to the known 234U(n, x) cross section. The compound nuclei of interest for this experiment were produced using inelastic alpha scattering. For example, 236U(a, a(prime)x) served as a surrogate for 235U(n, x); analogous reactions were considered for the other cross sections. Surrogate experiments determine the probabilities for the decay of the compound nuclei into the various channels of interest (fission, gamma decay) by measuring particle-fission (p-f) or particle?gamma (p?g) reaction spectra. By comparing the decay probabilities associated with the unknown cross section to that of a known cross section it is possible to obtain the ratio of these cross sections and thus determine the unknown, desired cross section.